Little Busters! follows a branching plot line which offers pre-determined scenarios with courses of interaction, and focuses on the appeal of the six female main characters by the player character, which increases to nine in Ecstasy. There are additional minigames added into the gameplay, such as battle sequences that resemble fighting games or baseball batting practice, which serve to give the characters experience, obtain accessories to use during battle, and improve their statistics. Both Little Busters! and Ecstasy ranked as the best-selling PC game sold in Japan for the time of their release, and Ecstasy would go on to sell over 100,000 units. Key went on to produce an adult spin-off called Kud Wafter in June 2010, which expanded on the scenario of Kudryavka Noumi, one of the heroines from Little Busters! and Ecstasy.

There have been 14 manga adaptations based on Little Busters! and Ecstasy published by ASCII Media Works, Kadokawa Shoten and Ichijinsha. Comic anthologies, light novels and art books were also published, as were several music albums. There have been two Internet radio shows hosted by the voice actors of Rin and Kyousuke Natsume and Kudryavka Noumi. J.C.Staff produced two anime television series and an original video animation series between 2012 and 2014.